Process for reclaiming rubber and cotton from waste



w P. E. YOUNG.

PROCESS FOR RECLAIMING RUBBER AND COTTON FROM WASTE. APPLICATION FILED SEPTI-19. 1918.

1,321,201 Patented Nov. 11, 1919.

UNITED s TEs PATENT OFFICE.

PHILIP E. YOUNG, or FAIRHAVEN, MASSACHUSETTS, ASSIGNOR 'ro AcUsHfIE'r rnocEss COMPANY; 1110., A CORPORATION OF NEW YORK.

PROCESS FOR BECLA-IMING RUBBER AND common rRoM wAsrE.

To all whom iii-may concern Be it lmown that I, PHILIP E. Young, of F airhaven, Massachusetts, have made certain new and useful Improvements in Proc- .esses for Reclaiming Rubber and Cotton from Waste, of which the following s a.

specification.

Many elforts have been made to reclaim Waste containing both cotton and rubber in such manner that both products will be obtained in forms of value. It has been pointed out in the application of Theodore F. Furness, Serial No. 163,520, filed April 20, 1917, that such a result can be obtained by disintegrating the fabric while in the presence of water and stripping the rubber from the threads and fibers resulting from such disintegration. My process relates to an improved method of disintegratlng the fabric and stripping the rubber from the threads and fibers, whereby material savings in operation are had and improved products are obtained.

As an illustration of my invention I Wlll describe it as applied to the uncured trimmings resulting from the manufacture of automobile tires that are known to the trade as friction scrap. This waste largely consists of strips of canvas with which the rubber is very closely incorporated. 1 The fabric in the strip is usually cut on the'bias so that if the strip is about half an inch wide the threads of the fabric willnot be substantially more than three-quarters of an inch long. Such a strip can very readily be unwoven into its separate threads but, if so unwoven, each thread will remain largely coated with rubber. I have discovered, however, that if such a strip is wet and subjected to a strenuous plcking operatlon which will tear out from the strip not the threads themselves but the strands of plies of the threads, the rubber will tend tocohere into small balls and the strands that are torn loose will be stripped practically clean bf rubber. It is, of course, impracticable to or particles.

In addition to. my improved method of progressively disintegratlng the fabric and stripping the rubber from thethreads and ers, my invention involves the use of novel methods of separating the rubber from the cotton. Y At the time the plies or strands are torn from the sheet and stripped of rubber I permit both the rubber and the cotton to be thrown-bythe picking machinery With considerable force and effect a separation by the different physical qualities of the two when so thrown. For example, if the two are thrown against an inclined boardthe cotton will slide down the board or, if Wet enough, W1ll stick to it, while therubber will bounce some distance away. So if both are thrown horizontally or in an upward direction the rubber will be thrown some distance away while the cotton will drop very near the point from which it is thrown. *These'efiects may also be aided by blowing or winnowing the cotton from the rubber. In other words I use the same force which helps in -pickingthe cotton from the rubber, to impart motion to both, and effect a separation through their difference-in mass and density.

In practising my invention I first pass the fridtionscrap through an ordinary cracker mill and sheet it in thepresence of water, and then feed it into a picker, such as the one diagrammatically represented in the ac- Specifieation of Letters Patent. Patented Nov, 11 1919,

Application filed September 19,1918. I Serial No. 254,761.

companying drawing. The wet'sheet formed I per minute up the surface of thefeed plate 5 against which it is held by the roll 6. As the sheet emerges from between the feed plate 5 and the roll 6, it comes in contact with the-teeth 7 of the cylinder 8. This cylinder rotates with a peripheral speed of from 3,000 to 5,000 feet per minute so that the teeth tear the plies or strands out of the fabric. As the cotton fibers are torn from the waste the rubber collects in small balls I The cotton and rubber together are thrown by the wheel 8 against the conveyor apr0n 9, and the rubber, having a considerable resiliency, bounces from the conveyer 9 into aconveniently placed receptacle 10, as shown in dotted lines. The co'tstick to the conveyer 9'and is carried over the upper end of this conveyer, from which it drops to the floor. The fine fibers of cotton that dry so rapidly that they do not stick to the conveyer 9 are largely carried over the top of this conveyer by the. draft created through the rotation of the wheel 8. Separation of the lint from the air current may be accomplished by inclosing the picker in a casing 11, in one side of which is a screen 12. While the material behind the conveyer 9 will be found to be largely cotton, and the bulk of the rubber will be in the receptacle 10, it is not to be understoodthat one pass through this picker will give a. clean separation. However, if the cotton is partly dried, one or two additional passes through the machine will leave it sufficiently clean to be garnetted and carded; in like manner the rubber should be resheeted and given a second pass-or more if necessary. After substantially all of the cotton is picked out ,of the rubber, the latter should be washed.

For this purpose I have found that while there is considerable difliculty in getting the rubber clean on an ordinary wash mill, very satisfactory results can be obtained by the use of the type of wash mill shown in United States Patent No. 1,267,492, of May 28, 1918.

To have my process operate to the. best advantage it is advisable that the sheet of ,rubber waste, on which the picker roll operates, be wet. It also will be found that this process is far more effective on rubber waste in which the rubber has a considerable degree of plasticity, such as uncured friction scrap. With other forms of waste it may be necessary, first, to subject the rubber to some well known plasticizing treatment, for I find it highly desirable that the waste should be in such condition that it will sheet and not pulverize upon being ground on a mill-a condition exactly the reverseof that desired by those who heretofore have attempted to separate cotton from rubber by winnowing or similar processes.

It will be readily apparent that my process can be carriedout on many types of machine other than the one suggested in the drawings and I do not wish to limit myself to the type of machine shown.

It is also apparent that this process can be used to separate w-ool or silk from rubber, if waste containing these materials is obtainable. The use of cotton is described in the claims and specification for illustrative purposes only, as this is substantially the only fibrous material found to any greatextent in rubber scrap.

What I claim is: Y

1. The process of separating cotton fiber or the like from rubber wast which con prises the steps of wetting the waste, pass-' ing the waste between rollers whereby the waste is, formed into a sheet, and feeding such sheet gradually to a high speed picker or the like from rubber waste which comprises the steps of forming the waste into a plastic sheet, feeding the sheet gradually to a high speed picker whereby threads and fibers of the cotton ai'e progressively torn from the sheet and simultaneously stripped of rubber and the plastic rubber is torn from the sheet in small aggregates, throwing the cotton and rubber through the air before opportunity is given for the material to reform into large aggregates, and separating cotton from the rubber during the movement imparted by such throwing.

3. The process of separating cotton fiber or the like. from rubber waste which comprises forming the waste into a moist plastic mass sucli that particles er rubber from the mass will tend to cohere to each other more readily than such particles will adhere to fibers of the fabric and comminuting such mass by the action of a picker whereby threads and fibers of the fabric are produced substantially free from rubber, and the rubher is produced in the form of small aggregates without the formation of rubber dust.

4. The process of separating cotton fiber or the like from rubber waste which comrises forming the waste into a plastic sheet, feeding the sheet gradually to a picker so thatthreads and fibers of cotton and small aggregates of the rubber are torn from the edge of the sheet, throwing the rubber and waste gradually to a high speed P101161" whereby the fabric is torn from the waste in the form of threads and fibers and the rubber is torn into small particles, throwing the. cotton and rubber together from the picker and separating cotton from the rub her by blowing the cotton out of its normal course.

PHILIP E. YOUNG. 

